But space boffins admit they are struggling to predict its path – as the gravity of other planets and stars are causing it to “wobble”.

NASA

RADAR: NASA is using radar to monitor 2003 SD220

“The reason they can become hazardous is that their trajectory can variate due to gravitational fields from planets or stars, or other objects.”

NASA

2003 SD220 may be even bigger than current estimates as much of its bulk is obscured by the darkness of space.

A team from NASA and the Arecibo observatory in Peurto Rico are preparing to carry out specialist radar observations of the astral boulder as it nears Earth from mid December.

It is expected to miss us by 6.7 million miles – which is close in cosmic terms – but a radiative effect that subtly changes the orbits of asteroids, known as the “Yarkovsky Drift”, means could hurtle closer to Earth.

The Idea Girl Severe Storm Predictions Warnings website claims its gravitational pull on Earth could trigger earthquakes or volcanoes – but there is no evidence of this from NASA.

GETTY

APOCALYPSE: This could happen if the asteroid strikes Earth

But the US space agency is watching the asteroid carefully.

It said: "These objects are monitored by NASA with contributions from others including amateurs.

"The reason they can become hazardous is that their trajectory can variate due to gravitational fields from planets or stars, or other objects."